<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <title>Title</title>
</head>
<body>
<script>
    let arr = [1, 2, 3, 4];
    let arr2 = ['a', 'b', ...arr, 'c', 'd'];
    console.log(arr2);
    
    // 剩余参数
    let [a, b, ...c] = arr;
    console.log(a, b, c);
</script>
</body>
</html>
